"Caveat Lector" wrote in message
news:kBY0f.370$i%.130@fed1read07...


"Brenda Ann" wrote in message
...

"David" wrote in message
...
On Wed, 05 Oct 2005 14:21:26 -0400, dxAce
wrote:



Caveat Lector wrote:

"bpnjensen" wrote in message
oups.com...
Why is it termed "SHORT" WAVE ?

Because it is shorter than medium wave, which in turn is shorter
than
long wave - back when these types of radio signals were the commonly
used wavelengths.

Of course, now with microwaves and picowaves, the name becomes much
less meaningful. In fact, the term H(igh) F(frequency), which seems
to
have replaced SW for many purposes, is not really accurate either.

Bruce Jensen


Very good Bruce -- indeed it is an ancient term carried over to this
very
day

From Wikipedia or google

Shortwave radio operates between the frequencies of 3,000 kHz and 30
MHz
(30,000 kHz) and came to be referred to as such in the early days of
radio
because the wavelengths associated with this frequency range were
shorter
than those commonly in use at that time. An alternate name is HF, or
high
frequency.

Some sources disagree on where shortwave begins. And, NASWA considers
shortwave
to begin at 2000 kHz.

dxAce
Michigan
USA

http://www.iserv.net/~n8kdv/dxpage.htm

All FCC bands break on 3s.


Ah, but can you tell us WHY they break on 3's?




OHHH good question

I suspect its because of the formula
wavelength = 300 / frequency in MHz

So when you divide out the 300/freq

It comes out in even metric units



e.g., ELF Extremely Low Frequency 3 - 30 Hz 100,000 - 10,000 km
SLF Super Low Frequency 30 - 300 Hz 10,000 - 1,000 km
ULF Ultra Low Frequency 300 - 3000 Hz 1,000 - 100 km
VLF Very Low Frequency 3 - 30 kHz 100 - 10 km
LF Low Frequency 30 - 300 kHz 10 - 1 km
MF Medium Frequency 300 - 3000 kHz 1 km - 100 m
HF High Frequency 3 - 30 MHz 100 - 10 m
VHF Very High Frequency 30 - 300 MHz 10 - 1 m
UHF Ultra High Frequency 300 - 3000 MHz 1 m - 10 cm
SHF Super High Frequency 3 - 30 GHz 10 - 1 cm
EHF Extremely High Frequency 30 - 300 GHz 1 cm - 1 mm



I guess, therefore I am

And the 300 in the formula has to do with the speed of light (radio Waves)
299,792,458 metres per second -- for practical purposes
300,000,000 meters per second

CL Guessing twice , confirms I am